Propionyl-salicylic acid and process of making same.



U ITED STATES PATENT QFFIOE.

OTTO BONHOEFFER, or ELBERFELD,

GERMANY, ASSIGNOR TO THE FAR- BENFABRIKEN OF ELBERFELD COMPANY, OF NEW YORK.

SPECIFICATION forming part of Letters Patent No. 656,435, dated August 21, 1900.

Application filed October 23, 1899.

Oo- OI-I2- on, OOOH.

According to my researches this product possesses valuable therapeutic properties and is suitable for use as a medicine for gouty rheumatism.

The process for producing my new compound consists in allowing propionic anhydride to act on salicylic acid in a suitable manner.

In order to carry out my process practically, I can, for instance, proceed as follows: Twenty parts, by weight, of salicylic acid are dissolved in forty parts, by weight, of propionic anhydride by heating on a water-bath. To the solution thus obtained 0.2 parts, by weight, of concentrated sulfuric acid are added with continuous stirring. The reaction begins instantly and is finished after further heating on the water-bath for about one hour under stirring. Subsequently the excess of anhydride and the propionic acid formed during the reaction are for the most part distilled over ata low temperature. The pure propionylsalicylic acid remains in the shape of white glittering small leaves melting at 95 centigrad e. The propionylsalicylic acid thus produced is soluble in water with difficulty. When boiled for a While with water, it is split up, salicylic and propionic acid being produced. It is likewise decomposed by the action of alkalies. The new acid thus produced CGH Serial No. 734,544- ($peoimens.)

pound possesses valuable therapeutic properties and can be used in medicine for gouty rheumatism.

Having now described my invention and in what manner the same is to be performed, what I claim as new, and desire to secure by Letters Patent, is-

1. The process for the production of propionylsalicylic acid which process consists in, first, allowing propionic anhydride to act on salicylic acid; secondly, isolating the soformed propionylsalicylic acid, substantially as hereinbefore described.

2. As a new article of manufacture the propionylsalicylic acid having the formula OTTO BONI-IOEFFER.

Witnesses:

R. E. JAHN, OTTO KONIG. 

